In the fractious debate over net neutrality, efforts to strike a compromise don't seem to be working. A proposal reportedly favored by a top U.S. regulator is drawing fire from groups on both sides of the issue, with 70 pro-net neutrality groups speaking up against the plan Friday.

Following a recent news report that U.S. Federal Communications Commission Chairman Tom Wheeler is leaning toward a so-called hybrid net neutrality proposal that regulates only a piece of broadband service, the groups advocating for strong net neutrality rules sent him a letter saying the plan would "threaten the open Internet."

While pro-net neutrality groups say a hybrid regulatory model wouldn't go far enough to protect Internet users, groups opposed to strong regulations say it goes too far. Verizon Communications, in a blog post this week, said a lighter regulatory approach would be the best way for the FCC to avoid a court challenge.

With a hybrid regulatory model, "the FCC has opened itself to credible challenges by all parties," wrote Randal Milch, Verizon's executive vice president for public policy. "Like a full move to [broadband regulation], the hybrid approach also fairly guarantees litigation."

One service would be retail broadband access, which would remain lightly regulated, and the second would be back-end transit service, which the FCC would reclassify as a regulated common carrier, similar to utility-style regulation for traditional telephone service. Mozilla proposed this type of hybrid regulatory model back in May.

Under the Mozilla plan, the FCC would divide last-mile broadband service into two "distinct relationships," one between the broadband provider and the end user, and the second a remote delivery service offered by the broadband provider to websites, cloud storage and other online services.

Mozilla asked the FCC to reclassify that remote delivery service as a common carrier subject to utility-style regulations under Title II of the Communications Act.

Many proponents of strong net neutrality regulations want the FCC to reclassify all broadband service as a regulated utility. A hybrid approach "would split the Internet in two, creating divisions in Internet access and enshrining the notion that people or companies sending information have protections against discrimination, while users have none against their own ISP," the letter said.

Among the groups signing Friday's letter are several heavily involved in the net neutrality debate, including Free Press, Fight for the Future and Demand Progress. Other groups signing include Greenpeace, Iraq Veterans Against the War, the Harry Potter Alliance and Million Hoodies.

The hybrid approach would leave "loopholes" open for broadband providers to negotiate traffic deals with Web content producers and is weaker than net neutrality rules backed by President Barack Obama, the letter said.

"This is not what the public wants or what President Obama promised the American public," the letter said. "Even the original authors of some of these approaches have said that full Title II reclassification is the better way forward, and ISPs like Verizon have already threatened lawsuits."

In addition to the letter, Free Press, Fight for the Future and other groups organized Thursday evening flash protests against the hybrid plan. Protests were staged in about 30 U.S. cities, and more than 100 people protested outside the White House in Washington, D.C., organizers said.

Meanwhile, groups on the other side of the net neutrality debate have also criticized a hybrid regulatory approach. Reclassifying any part of broadband "opens the door to FCC regulation of the heart of the Internet," said Berin Szoka, president of free-market think tank TechFreedom.

While Wheeler is under "enormous pressure" to adopt net neutrality rules, he should consider going to Congress and asking for new authority to craft the regulations, Szoka said in an email. While many in Congress would oppose Title II-based net neutrality rules, a "broad consensus" exists to give the agency some authority to enforce rules requiring broadband providers to be transparent about their network management practices and prohibiting them from blocking Web traffic, he said.

"Congressional Republicans have a strong incentive to demonstrate that they can govern responsibly," Szoka said. "And all sides of the tech industry desperately need this intractable fight over the FCC's authority to end."

Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's email address is grant_gross@idg.com.

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